Right to that white house in rome, italy. It broke at 5:00 a.M. A new trial for amanda knox. It stunned her and her family. Remember, she was acquitted almost 18 months ago of murder. This legal nightmare began years ago. It's continui her attorney ted simon will join us live in just a moment. He was the one who broke the news to amanda this morning. Let's get right to abc's lama hasan with the breaking developments. Reporter: Good morning to you. What a dramatic day. Italy's highest criminal court has ordered a retrial in the case of against amanda knox and her former boyfriend, rafaelle sollecito. Knox who lives and attends college in her hometown stayed up till 2:00 a.M. To hear her fate. She is incredibly sad. This morning a stunning reversal in the acquittal of amanda knox as she now will have to face an entirely new trial. More than 18 months since she was freed and after serving four years in a perugia jail both knox and her then boyfriend rafaelle sollecito are now back to step one. Both families' worst nightmares. She's shocked. Very sad. Thought this was the end of a nightmare but she's also very strong and she's willing to fight again. Reporter: The knox family released a statement saying it was painful to receive the news that the italian supreme court decided to send my case back for revision. Back in 2011 defense lawyers and experts revealed how evidence was contaminated by forensic teams. Reporter: And successfully argued their release with knox flying ho emto seattle and sollecito to southern italy but the prosecution hit back demanding a retrial arguing to the supreme court that the acquit wall was "a rare mix of violation of the law and illogicalness" saying the judge who acquitted them had "lost his way." A difficult day for both families and happens to be sollecito's 29th birthday. No word on whether knox and sollecito have had any contact since the news broke.

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